摘要
铜陵公铁两用长江大桥主桥为(90+240+630+240+90)m五跨连续钢桁梁斜拉桥,主梁采用双节间全焊桁片组拼钢桁梁结构。结合桥址处水文地理条件,对南岸边跨钢梁全顶推和双悬臂架设方案比选,确定南岸边跨采用全顶推方案。顶推施工方案为在边跨设置3处墩旁托架、2个临时墩,采用1 000t浮吊于4号墩墩旁托架主跨侧拼装30m导梁、边跨A0A5节段钢梁及架梁吊机,A6A24节段钢梁经架梁吊机起吊拼装后向边跨顶推架设。墩旁托架及临时墩立柱采用?1 400mm×22mm和?1 020mm×10mm两种规格钢管,在墩旁托架顶端设置对拉钢绞线,联结系采用?630mm×8mm和?426mm×6mm钢管;导梁采用三片桁结构,桁高和梁宽均与主梁相同;水平顶推设备为4台350t连续千斤顶,布置于4号墩墩旁托架边跨侧外立柱顶部。有限元计算及实践结果表明钢梁顶推过程中钢梁位移和应力满足要求。
The main bridge of Tongling Rail-cum-Road Changjiang River Bridge is a five-span continuous steel truss girder cable-stayed bridge with span arrangement of （90＋240＋630＋240＋ 90）m. The main girder adopts the steel truss structure assembled by double-section fully welded trusses. Given the hydrological and geological conditions at the bridge site, the two construction schemes for the girders in the south side spans were compared, including the fully incremental launching and the balanced cantilever erection method. The former was finally chosen. In the in- cremental launching scheme, pier-side brackets are installed at three locations in the side spans and two temporary piers are needed. The floating crane with a capacity of 1000 t was used to assemble the 30-m long launching nose on the brackets erected at pier No. 4 on the main girder side, the side span AOA5 steel girder section and the girder erection gantry. The A6A2 steel girder section was lifted and erected by the girder erection gantry and then incrementally launched towards the side span. Two types of steel pipes of Ф 400 mm×22mm and Ф 020 mm× 10 mm were used in the pier-side brackets and temporary pier columns, and atop of the pier-side brackets, pull-back steel strands were added. The lateral bracings adopt the Ф30 mm × 8 mm and Ф26 mm ×6 mm steel pipes. The launching nose is a three-truss structure with the same width and depth of the main girder. Four continuous jacks, each with capacity of 350 t, were used for the horizontal incremen- tal launching, which were placed on the top of the outside column at the pier-side brackets of the pier No. 4 on the side span side. The results of the finite element calculation demonstrate that the displacement and stress of the steel girder during the incremental launching of the steel girder meet the requirements.
出处
《世界桥梁》
北大核心
2015年第6期1-5,共5页
World Bridges
关键词
斜拉桥
钢桁梁
顶推施工
墩旁托架
临时墩
导粱
架梁吊机
有限元法
cable-stayed bridge
steel truss girder
incremental launching construction
pier-side brackets
temporary pier
launching nose
girder erection gantry
finite element method
